What the heck is Cracking?
Cracking - removing the copyright protection on software, mainly on games. Back in the day, games on floppy had elaborate protection schemes, often including bizzarely written discs that were impossible to duplicate on normal floppy drives and the infamous 'manual lookup' protection. Groups got a lot of prestige (heh heh) from doing '0day' releases, meaning the cracks were available on or before the official release date (this is still the case, although it's much easier with the internet -- back then there were couriers that would call numerous Bulletin Board Systems and upload the files). Generally they also added 'cracktros', ie intros that would play before the game loaded, featuring chip music, scrolltexts, and demo-like effects (plasma, rasterbars, fractal zoomers etc). This scene is still pretty active, but nowadays a lot of 'cracking' involves using CD cloning software and distributing legit CD-keys, ie stuff that's pretty damn easy to do. Cracktros are rarely seen any more, either. Hence the cracking 'scene' is kind of lame nowadays.
BTW - most of that 'leet speak' you see on the internet started out as a parody of the cracking scene. 'Warez kiddies' and couriers were considered the lamest part of the underground computing scene, and those who considered themselves on the highest rungs -- the hack/phreak crowd mainly -- poked a lot of fun at the crackers and especially those who didn't crack but merely couriered or downloaded games.